Pipeline leakage-sensing device

Abstract

A leakage-sensing device for installation adjacent to a pipeline configured for conveying liquid or gaseous chemical materials. The leakage-sensing device comprises a length of cable configured to transmit and back-reflect signals. The cable is communicable with a signal-measuring device. The entire length of cable is encompassed by a torsioned and tensioned coiled biasing means. The cable and the torsioned and tensioned coiled biasing means are embedded in a chemically frangible casing material. The chemically frangible material is selected for its structural instability when contacted with the selected chemical material to be conveyed within the pipeline thereby releasing the torsioned and tensioned biasing means which subsequently imparts bending and/or twisting and/or elongating and/or contracting forces to the cable thereby causing the cable to physically interfere with and/or deform and/or break the transmission and back-reflection of signals along the cable.

The invention claimed is: 
     
       1. A leakage-sensing device for installation adjacent to a transmission pipeline configured for conveying a selected material therein, said leakage-sensing device comprising:
 a first length of cable configured to transmit and back-reflect light energy therethrough, said cable communicable with a signal-generating device and a signal-measuring device; 
 a stressed coiled biasing element circumscribing said length of cable; and 
 a chemically frangible casing configured for encasing and embedding therein the length of cable circumscribed by the stressed coiled biasing element, said chemically frangible casing selected for its structural instability when contacted with said conveyed material thereby releasing the stress on said coiled biasing element. 
 
     
     
       2. A leakage-sensing device according to  claim 1 , wherein the first length of cable circumscribed by the stressed coiled biasing element and encased by the chemically frangible casing is splicable to a second length of cable configured to transmit and back-reflect signals therethrough thereby communicable with the first length of cable and a signal-generating device and a signal-measuring device, said second length of cable circumscribed by a stressed coiled biasing element and encased by a chemically frangible casing selected for its structural instability when contacted with said conveyed material. 
     
     
       3. A leakage-sensing device according to  claim 1 , wherein the first length of cable is a fiber optic cable. 
     
     
       4. A leakage-sensing device according to  claim 3 , wherein the fiber optic cable is cooperative with a fiber optic waveguide. 
     
     
       5. A leakage-sensing device according to  claim 1 , wherein the coiled biasing element is stressed by a force selected from the group comprising tensioning forces and stretching forces. 
     
     
       6. A leakage-sensing device according to  claim 1 , wherein the coiled biasing element is stressed by a force selected from the group comprising torsioning forces and compressive forces. 
     
     
       7. A leakage-sensing device according to  claim 1 , wherein the coiled biasing element is stressed by a plurality of forces selected from the group comprising tensioning forces, stretching forces, and compressive forces. 
     
     
       8. A leakage-sensing device according to  claim 1 , wherein the chemically frangible casing is thermostable in a temperature range between −70° C. to +70° C. 
     
     
       9. A leakage-sensing device according to  claim 8 , wherein the chemically frangible casing is structurally unstabilized when contacted with a material selected from the group comprising liquids and gases. 
     
     
       10. A leakage-sensing device according to  claim 9 , wherein the chemically frangible casing is structurally unstabilized when contacted with a liquid material selected from the group comprising water, alcohols, acids, bases, and hydrocarbon-containing fluids. 
     
     
       11. A leakage-sensing device according to  claim 10 , wherein the chemically frangible casing is structurally unstabilized when contacted with water. 
     
     
       12. A leakage-sensing device according to  claim 10 , wherein the chemically frangible casing is structurally unstabilized when contacted with an alcohol. 
     
     
       13. A leakage-sensing device according to  claim 10 , wherein the chemically frangible casing is structurally unstabilized when contacted with an acid. 
     
     
       14. A leakage-sensing device according to  claim 10 , wherein the chemically frangible casing is structurally unstabilized when contacted with a base. 
     
     
       15. A leakage-sensing device according to  claim 10 , wherein the chemically frangible casing is structurally unstabilized when contacted with a hydrocarbon fluid from the group comprising crude oil, refined oil, gasoline, diesel oil, and refined petroleum products. 
     
     
       16. A leakage-sensing device according to  claim 9 , wherein the chemically frangible casing is structurally unstabilized when contacted with a gaseous material from the group comprising methane, ethane, butane, propane, carbon dioxide, nitrogen, nitrous oxide, nitrous dioxide, ammonia, helium, hydrogen sulfide, and sulfur dioxide, and halides. 
     
     
       17. A leakage-sensing device according to  claim 9 , wherein the chemically frangible casing is structurally unstabilized when contacted with a mixture of gaseous material from the group comprising quantities of methane, ethane, butane, propane, carbon dioxide, nitrogen, nitrous oxide, nitrous dioxide, ammonia, helium, hydrogen sulfide, and sulfur dioxide, and halides. 
     
     
       18. A leakage-sensing device according to  claim 9 , wherein the chemically frangible casing is structurally unstabilized when contacted with methane. 
     
     
       19. A process for producing the leakage-sensing device of  claim 1 , the process comprising:
 circumscribing a length of cable configured to transmit and back-reflect light energy therethrough, said cable communicable with a signal-generating device and a signal-measuring device, with a coiled biasing element; 
 applying a stress to said coiled biasing element; 
 applying a viscous fluid material to encase said cable and said stressed coiled biasing element circumscribing said cable, said viscous fluid material configured to dry after application to form a chemically frangible casing that loses its structural stability when contacted with a selected material. 
 
     
     
       20. A process according to  claim 19 , wherein the cable is configured to transmit and back-reflect laser energy. 
     
     
       21. A process according to  claim 19 , wherein the cable is a fiber optic cable. 
     
     
       22. A process according to  claim 21 , wherein the fiber optic cable is cooperative with a fiber optic waveguide. 
     
     
       23. A process according to  claim 19 , wherein the coiled biasing element is stressed by a force selected from the group comprising tensioning forces and stretching forces. 
     
     
       24. A process according to  claim 19 , wherein the coiled biasing element is stressed by a force selected from the group comprising torsioning forces and compressive forces. 
     
     
       25. A process according to  claim 19 , wherein the coiled biasing element is stressed by a plurality of forces selected from the group comprising tensioning forces, stretching forces, and compressive forces. 
     
     
       26. A process according to  claim 19 , wherein the chemically frangible casing is thermostable in a temperature range between −70° C. to +70° C. 
     
     
       27. A process according to  claim 26 , wherein the chemically frangible casing is structurally unstabilized when contacted with a liquid material selected from the group comprising water, alcohols, acids, bases, and hydrocarbon-containing fluids. 
     
     
       28. A process according to  claim 26 , wherein the chemically frangible casing is structurally unstabilized when contacted with a hydrocarbon fluid from the group comprising crude oil, refined oil, gasoline, diesel oil, and refined petroleum products. 
     
     
       29. A process according to  claim 26 , wherein the chemically frangible casing is structurally unstabilized when contacted with a gaseous material from the group comprising methane, ethane, butane, propane, carbon dioxide, nitrogen, nitrous oxide, nitrous dioxide, ammonia, helium, hydrogen sulfide, and sulfur dioxide, and halides. 
     
     
       30. A process according to  claim 26 , wherein the chemically frangible casing is structurally unstabilized when contacted with a mixture of gaseous material from the group comprising quantities of methane, ethane, butane, propane, carbon dioxide, nitrogen, helium and hydrogen sulfide. 
     
     
       31. A process according to  claim 26 , wherein the chemically frangible casing is structurally unstabilized when contacted with methane